To address climate change and move towards the goal of carbon neutrality, Prof. Daniel Lau, Chair Professor of Nanomaterials and Head of the Department of Applied Physics, and his team have developed a durable, highly selective and energy-efficient carbon dioxide (CO₂) electroreduction system that can convert CO₂ into ethylene, one of the most in-demand chemicals globally which is mainly used in the manufacture of polymers for industrial purposes to provide an effective solution for reducing CO₂ emissions. Their research was published in Nature Energy and won a Gold Medal at the 48th International Exhibition of Inventions Geneva.

The research team adopted the method of electrocatalytic CO₂ reduction – using green electricity to convert carbon dioxide into ethylene, providing a more environmentally friendly alternative and stable ethylene production. The team is working to promote this emerging technology and bring it closer to mass production, closing the carbon loop and ultimately achieving carbon neutrality.

Prof. Lau’s innovation is to dispense with the alkali-metal electrolyte and use pure water as a metal-free anolyte to prevent carbonate formation and salt deposition. The team denoted their design the APMA (A: anion-exchange membrane, P: proton-exchange membrane, MA: resulting membrane assembly) system. When an alkali-metal-free cell stack containing the APMA and a copper electrocatalyst is constructed, it produces ethylene with a high specificity of 50%. It can also operate for over 1,000 hours at an industrial-level current of 10A, which is a very significant increase in lifespan over existing systems. The APMA cell design underpins a transition to green production of ethylene and other valuable chemicals, contributing to reducing carbon emissions and achieving the goal of carbon neutrality.

The project is a collaboration with researchers from the University of Oxford, the National Synchrotron Radiation Research Centre of Taiwan and Jiangsu University.